(EN) The invention concerns a method of carrying out continuous preparation processes on tightly meshing extruders rotating in the same sense, such as double screw and multi-shaft screw-type extruders. The extruder is operated at a screw speed of rotation of at least 800 rpm whilst the so-called "torque density" (Md/a<3>) which can be induced is increased by at least 11 Nm/cm<3> and the ratio between the screw outer diameter and screw inner diameter (Da/Di) is at least 1.5.